1. Technical Field
The present invention relates an auto sheet feed device with a variable resistance plate and, more particularly, to an auto sheet feed device for office automation systems adopting a separation method for the variable resistance plate to improve the reliability of the paper feed. The paper entry angle and the angle of the separation resistance plate are maintained identical by the variable device of the resistance plate angle according to the variation of the paper quantity.
2. Related Art
Generally, many devices are used in office automation systems. A printer is an output device for making documents by outputting, in the form of letters on paper sheets, printed data, letters or graphics from a computer. A copier is a device for copying data in the form of documents or images as they appear. A facsimile transmits needed data to people over long distances in order that they can see the data directly.
Conventionally, data or files composed by users with computers become documents by being printed with various kinds of printers. However, the present invention will be exemplified with an ink jet printer. In such a printer, the pressure within a cartridge rises and bubbles occur like soap bubbles if ink stored in a cartridge is heated. The ink jet printer prints by forming letters and attaching them to the paper by jetting bubbles occurring at that time through a nozzle.
Numbers of nozzles used in an ink jet printer generally amount to about 64 pieces, and the resolution of pictures is usually about 300.about.1200 DPI (Dot Per Inch). Also color printing is possible with some sorts of installed cartridges.
In such office automation devices, feeding of paper in response to a print control signal is performed in a reliable manner in dependence on the angle between a resistance plate which separates paper from the feeder and the paper loaded in the feeder itself. This is complicated by the fact that, in the usual feeder, as paper is withdrawn, the entry angle of the paper changes due to rising of the loading plate on which the paper is loaded. Therefore, there is a need for the development of a device which compensates for the change in the entry angle of the paper by adjusting or varying the angle of the resistance plate.